US3775662A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Constant frequency power inverter having silicon controlled rectifier multibridge inputs for output wave shaping with variable phase control for overload conditions
Assignee: Bendix Corp
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Filing: 1971-12-07
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Granted: 1973-11-27
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Expires: 1991-12-07
Abstract
Abstract A static inverter for converting D. C. power to three phase A. C. power which has a bridge circuit connected to the D. C. power source and including a plurality of silicon controlled rectifiers turned on by logic signals from a logic control circuit. A commutating circuit has silicon controlled rectifiers turned on by logic signals from the logic control circuit to control a single LC network to provide reverse polarity voltages to all the silicon controlled rectifiers in the bridge circuit to turn them off. Three phase A. C. power is provided by transformers having their primary windings connected to the bridge circuits and their secondary windings connected in series. The static inverter may include a plurality of bridge circuits and the relative phases of the logic signals to the bridge circuits is shifted to vary the phase relationship of the currents from the bridge circuits to change the amplitude of the three phase A.C. power from the transformers to avoid overloading the inverter in case of a short circuit in the load.
Inventors
- 👤 A Compoly
- 👤 R Kautz
- 👤 R Eckenfelder
- 👤 F Foerch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 06:06
CPC Classifications
H; H02; H02M; H02M7/00; H02M7/42; H02M7/44; H02M7/48; H02M7/483; H02M7/49; H02M7/505; H02M7/515; H02M7/5152
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
138 words
A static inverter for converting D.C. power to multiphase A.C. power, comprising at least two bridge circuits connected to the D.C. power source and including a plurality of switching means, a logic control circuit connected to the bridge circuits and providing signals for controlling the switching means in predetermined sequence to conduct current, summing means connected to the bridge circuits and energized by currents therefrom and providing the multiphase A.C. power, the logic control circuit having means for changing the relative phase relationship of the logic signals to the bridge circuits the discrete steps to vary the phase relationship of the currents from the bridge circuits, and fault detecting means for sensing an overload and controlling the phase changing means to reduce the multiphase A.C. power from the summing means to a safe value when an overload occurs.
Claim 2
Dependent Claim
138 words
A static inverter for converting D.C. power to multiphase A.C. power, comprising at least two bridge circuits connected to the D.C. power source and including a plurality of switching means, a logic control circuit connected to the bridge circuits and providing signals for controlling the switching means in predetermined sequence to conduct current, summing means connected to the bridge circuits and energized by currents therefrom and providing the multiphase A.C. power, the logic control circuit having means for changing the relative phase relationship of the logic signals to the bridge circuits the discrete steps to vary the phase relationship of the currents from the bridge circuits, and fault detecting means for sensing an overload and controlling the phase changing means to reduce the multiphase A.C. power from the summing means to a safe value when an overload occurs.
Claim 3
Dependent Claim
47 words
An inverter as described in claim 1 in which the phase changing means upon removal of the overload changes the relative phase relationship of the logic signals to the bridge circuits in discrete steps to increase the three phase A.C. power from the transformer means to normal.
Claim 4
Dependent Claim
192 words
A static inverter for converting D.C. power to multiphase A.C. power, comprising at least two bridge circuits connected to the D.C. power source and including a plurality of switching means, a logic control circuit connected to the bridge circuits and providing signals for controlling the switching means in predetermined sequence to conduct current, and summing means connected to the bridge circuits for summing the currents therefrom and providing the multiphase A.C. power, fault detection means, means responsive to the fault detection means for reducing power to the inverter substantially to zero in response to a fault, the logic control circuit having means for instantaneously shifting the relative phases of the logic signals to the bridge circuits 180* out of phase when power to the inverter is reduced substantially to zero to vary the phase relationship of the currents from the bridge circuits and change the amplitude of the multiphase A.C. power from the summing means substantially to zero, and for shifting the relative phases of the logic signals in discreTe steps to restore the multiphase A.C. power from the transformer means to a safe value when power is restored to the inverter.
Claim 5
Dependent Claim
192 words
A static inverter for converting D.C. power to multiphase A.C. power, comprising at least two bridge circuits connected to the D.C. power source and including a plurality of switching means, a logic control circuit connected to the bridge circuits and providing signals for controlling the switching means in predetermined sequence to conduct current, and summing means connected to the bridge circuits for summing the currents therefrom and providing the multiphase A.C. power, fault detection means, means responsive to the fault detection means for reducing power to the inverter substantially to zero in response to a fault, the logic control circuit having means for instantaneously shifting the relative phases of the logic signals to the bridge circuits 180* out of phase when power to the inverter is reduced substantially to zero to vary the phase relationship of the currents from the bridge circuits and change the amplitude of the multiphase A.C. power from the summing means substantially to zero, and for shifting the relative phases of the logic signals in discreTe steps to restore the multiphase A.C. power from the transformer means to a safe value when power is restored to the inverter.
Claim 6
Dependent Claim
181 words
A static inverter for converting D. C. power to multiphase A.C. power comprising: a bridge circuit connected to the D.C. power source and including a plurality of silicon controlled rectifiers, a logic control circuit connected to the bridge circuit and providing signals for turning on the silicon controlled rectifiers in predetermined sequence to conduct current, a commutating circuit connected to the bridge circuit and to the logic control circuit and including an L.C. network and switching means, the logic control circuit providing signals for operating the switching means in predetermined sequence to charge and discharge a capacitor in the L.C. network to provide reverse polarity voltages to the silicon controlled rectifiers in the bridge circuit to turn them off, the commutating circuit being connected to a source of commutating voltage, and a condenser and a diode connected across the commutating voltage source to assist in recharging the capacitor in the L.C. network when the switching means in the commutating circuit are operated, and transformer means connected to the bridge circuit and energized by current therefrom and providing the multiphase A.C. power.
Claim 7
Dependent Claim
181 words
A static inverter for converting D. C. power to multiphase A.C. power comprising: a bridge circuit connected to the D.C. power source and including a plurality of silicon controlled rectifiers, a logic control circuit connected to the bridge circuit and providing signals for turning on the silicon controlled rectifiers in predetermined sequence to conduct current, a commutating circuit connected to the bridge circuit and to the logic control circuit and including an L.C. network and switching means, the logic control circuit providing signals for operating the switching means in predetermined sequence to charge and discharge a capacitor in the L.C. network to provide reverse polarity voltages to the silicon controlled rectifiers in the bridge circuit to turn them off, the commutating circuit being connected to a source of commutating voltage, and a condenser and a diode connected across the commutating voltage source to assist in recharging the capacitor in the L.C. network when the switching means in the commutating circuit are operated, and transformer means connected to the bridge circuit and energized by current therefrom and providing the multiphase A.C. power.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-26 | 1977-05-28 | 1977-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-26 | 1981-05-28 | 1981-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-26 | 1985-05-28 | 1985-11-27 | $7700.00 | Window Closed / Lapsed |